Method and apparatus for firing furnaces



C. A. KELLOGG.

A METHOD AND APPARATUS FOR FIRING FURNACES.

APPLICATION FILED FEB. 9. I920.

Patented Jan. 10, 1922.

5 SHEETS-SHEET I.

\Q ullllll w anuwltoz C. A. KELLOGG.

METHOD AND APPARATUS FOR FIRING FURNACES.

APPLICATION FILED FEB. 9. I920.

Patented Jan. 10,192..

C. A. KELLOGG METHOD AND APPARATUS FOR FIRING FURNACES. APPLICATION FILED FEB. 9. 1-920.

1302373, Patented Jan; 10,1922.

C. A. KELLOGG.

METHOD AND APPARATUS FOR FIRING FURNACES.

APPLICATION FILED FEB. 9, I920.

-C. A. KELLOGG.

METHOD AND APPARATUS FOR FIRING FURNAGES. APPLICATION FILED FEB. 9. 1920.

1,402,773, 7 I Patented Jah. 10, 192 2;

5 SHEETS-SHEET 5.

. UNITED STATES CHESTER A. KELLOGG, 0F BARTONVILLE,

PATENT OFFICE.

ILLINOIS, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO THE UNION TRUST COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO, AND JOHN A. CHAPMAN, TRUSTEES, OF CHICAGO, ILLINOIS.

, METHOD AND APPARATUS FOR- FIRING FURNACES.

Specification of Letters Patent.

Patented J an. 10, 1922.

Application filed February 9, 1920., Serial No. 357,208.

To aZZ'w/wmc't concern: I Be it known that I, Cnns'rnn A. KnnL-ose, a citizen of the United States, residing at Bartonville, in the county of Peoria and State of Illinois, have invented new and useful Improvements in Methods and Apparatus for Firing Furnaces, of which the following is a specification.

This invention has reference to a method of converting gas fired regenerative furnaces to furnaces in which fuels which do not rescription to the use of liquid fuels, and. still further for the sake of brevity, to oil.. That the invention may be more fully understood, reference is had to the accompanying draw ings forming a part of this description, showing a well known type of gas fired regenerative furnace with the preferred em bodiment of my invention applied thereto.

Fig. 1 is a diagrammatic view showing the opposite ends of a gas fired regenerative furnace with the air and gas systems,'and stack, or waste heat boiler connected thereto, the arrangement, showing the furnace to be fired with gas;

Fig. 2 is ardiagrammatic view somewhat similar to Fig. 1, but showing the preferred furnace arrangement when fired with oil and with my invention applied to permit conversion from gasffiredto oil fired;

' Fig. 3ris a. vertical longitudinal sectional view throughthe left hand end of the furnace looking at Fig. 1, to show the arrange.- ment of the gas and air slag pockets,.the.up takes and the gasand air ports connecting the uptakes with the furnace proper;

Fig. 4 is a vertical cross-section of. the furnace looking toward one. end, and-is approximately the same as would appear if taken alon the line 4-4 of Fig. 5 in the direction 0% the arrow, and

Fig. 5 is a cross-sectionin plan. throu h the gas and air slag pockets, and 1s as t e same would appear if taken on the line 5-5 Fig. l in the direction of the arrow.

Like characters of reference denote corresponding parts throughout the figures.

Those skilled in the art to which this in vention pertains will readily understand the construction of the furnace shown, and its intended operation when gas fired, and those who have had experience with oil firing will understand the attempts which have been made to convert such a furnace, as shown, from gas fired to oil fired, without the necessity of specific reference to the various elements of the furnace and their uses; but that a very clear and concise understanding may be had of my method of conversion from a gas fired to an oil fired furnace, and the use of the apparatus, I shall very briefly point out the various elements of the furnace and the direction of the gas and air, as well as the oil when using the furnace.

Such a furnace as I have shown includes the opposite end gas checker chambers 1 and 1 communicatingwith gas slag pockets 2 and 52 respectively, which in turn commun cate with gas uptakes 3 and 3 respectively; the air checker chambers 4: and t which communicate with the air slag pockets 5 and 5 respectively, which in turncommunicate with the air uptakes 6 and 7,. and 6 and 7 respectively. 8 and'8 designate the gas sysv ofdirection of the gas. and air to the respective gas and air checker chambers 1 and l. and 1 and P.

By the arrangement of the system as illus trated in Fig. 1 (the furnace being. fired with gas) the gas, enters the gas. checker in the art, to. permit the alternate reversal chamber 1, passes through the slag pockets v 2,. and up through the uptakes 3. into the body of the furnace mingling with air as it enters the body offth'e. furnace, which said air enters through the air checker chamber 4:, thence into the slag pocket 5 and up through the airuptakes 6 and 7. The'prodnets of combustion pass through the furnace proper, and the waste gases exhaust down through the air uptakes 6 and 7 and the gas uptakes 3, through the gas and air checker chambers 1 and 4 and out through the stack or the waste heat boiler 18. This operation continues for about fifteen minutes, when the reversing valves 10, 10 and 11 are shifted into the dotted position shown in Fig. 1, when the direction of intake of gas and air and the exhaust of the waste gases is changed-4. e. the gas then enters the furnace through the checker chamber 1, the slag pocket 2 and through the gas uptake 3, such gas mixing with the air which enters the furnace through the air checker chamber 4, slag pocket 5 and up through the air uptakes 6 and 7. The products of combustion, or waste gases leaving the furnace through the gas and air uptakes 8, 6 and 7 respectively, and through the gas and air slag pockets 2 and 5 respectively, the gas and air checker chambers 1 and 1 respectively and out through the stack 12 or waste heat boiler 13. This operation continues for approximately fifteen minutes, when the cycle is again reversed, and so on until the heat is ready to tap.

In Fig. 2, which is a diagrammatic illustration showing the furnace converted to oil burning, I have shown the gas uptakes 3 and 3 blocked off and also shown the gas and air slag pockets 2 and 5, and 2' and 5 connected by flues 14 and 141 communicating with said slag pockets through the slag pocket bulk-heads. With this arrangement air'may be introduced through either of the systems 8 and 9 or S and 9, which entering through the checker chambers will pass into the slag pockets and into thebody of the furnace through the uptakes 6 and 7 or 6 and 7 the air which passes into the slag pockets 2 and 2, not finding egress through the uptakes 3 and 3 will pass into and through the fines T14 and 14 commingling with the air entering through checker chambers 1 and 1 and passing into the body of the furnace through either of the uptakes 6 and 7 or 6 and 7 to assist in the proper combustion of the oil which is forced into the furnace under pressure, in a manner and 7 v for purposes more fully to be explained;

Referring toFig. 3, I have shown arefractory wall 15 which blocks off the open-- ing providing communication between the 7 gas uptake .3 and a gas port 16, and have removed the end bulkhead at the point'17 of the gas port 16 to provide for the insertion or placing of the oil burner 18'suitably connected with a source of oil supply. In

the forward end of the gas port 16, I have shown a-refractory partition 19 provided with an opening 20 through which the nozzle of the oil burner 18 protrudes for the discharge of the oil into-the body 21rof the one.

the furnace, (see Fig.

of such fine or flues, as will be understood.

The last foregoing description shows the manner and form (Fig. 3) in which the upper ends of the gas uptakcs 3 and 3 -are blocked off, together with the removal of the wall at 17 to permit the introduction of the oil burner, or burners in the ports ordinarily used for the introduction of gas into the furnace proper. With such changes, as I have previously explained, air will be introduced through the slag pockets 2 and 5, or 2 and 5 which passes into the furnace through the port 22; the oil forced into the burner 18 meeting the air at the point of combustion where the air and oil enters the body 21, of

Should it be desirable or expedient to ire-convert thefurnace from oil burning to gas burning, all that. is necessary to do is to remove the refractory wall 15, the partition 19, withdraw the oil burner 18, again block up the end of the port 16 at the point 17 and block up the bulk-heads of the gas'and air slag pockets at the point where the necks 23 of the fines 1 1 or 14c comunicate with said slag pockets.

I aim with my method of conversion from gas to oil burning and apparatus for this purpose to make the change from gas to oil burning without interfering withv the operation of the furnace unless it be for the very shortest possible space of time and without the necessity of cooling down or stopping the furnace entirely. I do not claim to being the first to convert a gas fired regenerative furnace to an oil burning fur nace, except by a method and means which will prevent the complete shutting down of the furnace and at a great loss of time and money. In otherwords, by my method and means, I do the work so expeditiously as not only to sav'ein the operation, which is very material from .a financial viewpoint, but during such change am able to operate continuously, and to this extent increase the The reason for increased production under the conditions which I have stated is by reason of the fact that fiues 14 and 14 permit of enough ingress and egress of air and waste gases so thatan ample amount of fuel may be burned at all times.

I will now describe the steps employed when changing the furnace from gas fired to oil'fired without the necessity of shutting down or cooling the furnace. lVe will as sume that the system of operation is that shown in the diagrammatic view Fig. 1. Both flues Hand 14 and connected necks 23 are constructed to the point of breaking down parts of the slag pocket bulk-headsto connect the fines by means of the necks 23 with said slag pockets. During the interval of time when the furnace is fired with gas passing into the checker chamber 1, the wall at 17 of the opposite gas port from that in which the gas is entering the furnace, is removed and a suitable shield, not. shown, is

inserted into the gas port to block the inner port to permit the placing of the refractory wall or partition 15 is removed and the partition 19 inserted and the oil burner 18 placed in position. This done the firing of the furnace is accomplished with the use of oil in place of gas on this end of the furnace. Now during the interval of time when the first oil burner is used the gas port at the opposite end of the furnace is blocked oil in the manner previously described and the gas uptake covered with a refractory wall to permit the introduction of the oil burner at that end of the furnace the products of combustion passing out through the air port, as previously described. During this work parts of the bulk-heads of the slag pockets are removed and the fiues 14 and 14: are connected thereto through the communicating necks 23. We now have the furnace completely changed from gas fired to oil fired and without any appreciable interruption to the operation of the furnace and the production of steel.

One of the plans previously devised for converting a gas fired furnace to an oil fired furnace which has come to my attention is to cut an opening through the partition walls 24 separating the gas and slag pockets 2 and 5 and 2 and 5 and block off the upper end of the gas uptakes by a refractory partition, such as I have shown at 15. The very serious objection to this manner of accomplishing this purpose is that the work of removing a part of the partition walls 7 -24: is done on the interior of the furnace,

whereas my work is all done exteriorly of the furnace. To remove a sectionof the partition walls 2 f it goes without saying that the furnace must be completely shut down and permitted to cool several daysbefore workmen can enter the slag pockets,

which to say the least is a very expensive operation, particularly by reason of the loss of production. Then again if it is desired to reconvert the furnace from an oil fired to a gas fired approximately the same amount of time must be consumed, and the furnace shut down to permit the openings in the partition walls 24 to be re-blocked, and experience has shown that it is extremely difficult to make the partition walls gas tight,

resulting in the burning of the gas and air in the slag pockets and destroying the refractory walls of slag pockets, as well as the uptakes. The cooling down of the furnace adds a further costly delay. Another form of converting from gas fired to oil fired which has come to my attention is to pro- .vide water-cooled oil burners which are 'inserted into the gas ports without blocking the gas uptakesa The serious objection to this method resides in the fact that the waste gases or products of combustion pass through the air portsalone as in my case, and it is found that the water-cooling reduces the temperature of the oil, thereby reducing the heat and seriously impairing the efficiency of the furnace as an oil burning furnace.

Instead of using a water-cooled burner it has been attempted to burn oil through an ordinary type of oil burner, but this is objectionable for the reason that the intense heat produced by the waste gases or products of combustion makes it necessary to remove the burners at opposite ends of the furnace during each reversal of the furnace. This method is so inadequate that. its use has been very limited if not entirely done away with. c

While I have preferred to disclose the invention in connection with the use of fuel oil, it is apparent that I may use other concentrated fuels without departing from the spirit and scope of the invention.

What I claim is 1. A method of converting a gas fired regenerative furnace to a furnace suitable for burning more concentrated fuels, which consists in connecting the air and gasv systoms of the furnace exteriorly of the furnace, closing the usual gas ports, and introducing concentrated fuel supplying means into the furnace.

2. A method of converting a gas fired regenerative furnace to an oil fired furnace, which consists in connecting the gas and air slag pockets of the furnace exte- Cil riorly of the furnace, closing the usual gas uptalres and gas ports, and introducing liquid fuel supplying means into the furnace through the gas ports.

3. A method of converting a gas fired regenerative furnace to an oil fired furnace, which consists in connecting the gas and air slag pocketsthrough their bulkheads, closing the usual gas uptakes and gas ports to eliminate the egress of the products of combustion and the ingress of the supplied gas, respectively, and introducing liquid fuel supplying means into the furnace.

.4. A method of converting a gas fired regenerative furnace to an oil fired furnace, which consists in removing portions of the bulkheads of the gas and air slag pockets and establishing communication between said gas and air slag pockets through the resulting openings, closing the usual gas uptakes and gas ports, and introducing liquid fuel supplying means into the furnace through the gas ports.

5. In a regenerative furnace, in combination with the gas and air slag pockets, gas uptakes and gas ports, a flue providing means of'communication between said slag pockets eXt-eriorly of the furnace, means for closing the gas uptakes and gas ports against-egress and ingress respectively, and oil burners arranged in said gas ports and communicating with the interior of the furnace and also connected to a source of supply.

a 6. In a regenerative furnace, in combina tion with the gas and air slag pockets, gas uptakes and gas ports, a flue providing means of communication between said slag pockets exteriorly of the furnace, means closing the upper ends of the gas uptakes, a partition closing the inner end of each gas port and provided with an opening therein, and an oil burner in each gas port, said burners having their discharge ends protrudingthrough the openings in said ports and connected at their opposite ends with a source of oil supply.

7. In a regenerative furnace, in combination with the gas and air supply systems, and gas uptakes and gas ports thereof, a flue for each gas and air supply system located externally thereof, and communicating means between said flues and gas and air supply systems respectively, means for closing the gas uptakes and gas ports against egress and ingress respectively, and oil burners arranged in said gas ports and communicating with the interior of the furnace at their inner ends and connected with an oil supply at their outer ends.

8. In a regenerative furnace, in combination with the gas and air supply systems and gas ports thereof, means connecting saidgas and air supply systems exteriorly of the furnace, means for closing communication between said gas and air supply systems and said gas ports, means for closing the gas ports against ingress, and concentrated fuel burners arranged in said gas ports and communicating with the interior of the furnace and also. connected to a, source of supply.

' CHESTER A. KELLOGG. 

